Introduction San Andreas Fault: an Overview
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Strike and Dip Refer to the Orientation Or Attitude of a Geologic Feature. The
Name__________________________________ 89.325 – Geology for Engineers Faults, Folds, Outcrop Patterns and Geologic Maps I. Properties of Earth Materials When rocks are subjected to differential stress the resulting build-up in strain can cause deformation. Depending on the material properties the result can either be elastic deformation which can ultimately lead to the breaking of the rock material (faults) or ductile deformation which can lead to the development of folds. In this exercise we will look at the various types of deformation and how geologists use geologic maps to understand this deformation. II. Strike and Dip Strike and dip refer to the orientation or attitude of a geologic feature. The strike line of a bed, fault, or other planar feature, is a line representing the intersection of that feature with a horizontal plane. On a geologic map, this is represented with a short straight line segment oriented parallel to the strike line. Strike (or strike angle) can be given as either a quadrant compass bearing of the strike line (N25°E for example) or in terms of east or west of true north or south, a single three digit number representing the azimuth, where the lower number is usually given (where the example of N25°E would simply be 025), or the azimuth number followed by the degree sign (example of N25°E would be 025°). The dip gives the steepest angle of descent of a tilted bed or feature relative to a horizontal plane, and is given by the number (0°-90°) as well as a letter (N, S, E, W) with rough direction in which the bed is dipping. -
2016 Hayward Local Hazard Mitigation Plan
EARTHQUAKE SEA LEVEL RISE FLOOD DROUGHT CLIMATE CHANGE LANDSLIDE HAZARDOUS WILDFIRE TSUNAMI MATERIALS LOCAL HAZARD MITIGATION PLAN 2 016 CITY OF heart of the bay TABLE OF CONTENTS TABLE OF FIGURES ......................................................................................................................... 4 TABLE OF TABLES .......................................................................................................................... 4 EXECUTIVE SUMMARY 5 RISK ASSESSMENT & ASSET EXPOSURE ......................................................................................... 6 EARTHQUAKE ................................................................................................................................. 6 FIRE ............................................................................................................................................... 6 LANDSLIDE ..................................................................................................................................... 6 FLOOD, TSUNAMI, AND SEA LEVEL RISE .......................................................................................... 6 DROUGHT ....................................................................................................................................... 6 HAZARDOUS MATERIALS ................................................................................................................. 7 MITIGATION STRATEGIES ............................................................................................................... -
Hildebrand Department of Petroleum and Geosystems Engineering Page
Hildebrand Department of Petroleum and Geosystems Engineering THE UNIVERSITY OF TEXAS AT AUSTIN Cockrell School of Engineering Standard Resume FULL NAME: Hilary Clement Olson TITLE: Senior Lecturer DEPARTMENT: Hildebrand Department of Petroleum and Geosystems Engineering EDUCATION: Stanford University Geology Ph.D. Summer 1988 University of Notre Dame Earth Sciences B.S. Spring 1983 Université Catholique de L'Ouest Diplôme de Langue Française Spring 1981 CURRENT AND PREVIOUS ACADEMIC POSITIONS: The University of Texas at Austin Center for Petroleum and Program September 2015 - Present Geosystems Engineering Manager The University of Texas at Austin Hildebrand Department of Sr. Lecturer September 2019 – present Petroleum and Geosystems Lecturer January 2013 – August Engineering 2019 The University of Texas at Austin Center for Petroleum and Research September 2013 – August Geosystems Engineering Associate 2015 The University of Texas at Austin Department of Geological Lecturer January 2011 – May 2013 Sciences The University of Texas at Austin Institute for Geophysics Research May 2007 – August 2013 Scientist Associate V Huston-Tillotson University Special Topics in the Instructor January 2006 – May 2006 Geosciences The University of Texas at Austin Institute for Geophysics Research September 1998 – May Associate 2007 The University of Texas at Austin Institute for Geophysics Research June 1996 – August 1998 Fellow The University of Texas at Austin Department of Geological Lecturer January 1996 – May 1996 Sciences The University of Texas -
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A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans Robert W. BOESSENECKER Department of Geology, University of Otago, 360 Leith Walk, P.O. Box 56, Dunedin, 9054 (New Zealand) and Department of Earth Sciences, Montana State University 200 Traphagen Hall, Bozeman, MT, 59715 (USA) and University of California Museum of Paleontology 1101 Valley Life Sciences Building, Berkeley, CA, 94720 (USA) [email protected] Boessenecker R. W. 2013. — A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans. Geodiversitas 35 (4): 815-940. http://dx.doi.org/g2013n4a5 ABSTRACT e newly discovered Upper Miocene to Upper Pliocene San Gregorio assem- blage of the Purisima Formation in Central California has yielded a diverse collection of 34 marine vertebrate taxa, including eight sharks, two bony fish, three marine birds (described in a previous study), and 21 marine mammals. Pinnipeds include the walrus Dusignathus sp., cf. D. seftoni, the fur seal Cal- lorhinus sp., cf. C. gilmorei, and indeterminate otariid bones. Baleen whales include dwarf mysticetes (Herpetocetus bramblei Whitmore & Barnes, 2008, Herpetocetus sp.), two right whales (cf. Eubalaena sp. 1, cf. Eubalaena sp. 2), at least three balaenopterids (“Balaenoptera” cortesi “var.” portisi Sacco, 1890, cf. Balaenoptera, Balaenopteridae gen. et sp. indet.) and a new species of rorqual (Balaenoptera bertae n. sp.) that exhibits a number of derived features that place it within the genus Balaenoptera. is new species of Balaenoptera is relatively small (estimated 61 cm bizygomatic width) and exhibits a comparatively nar- row vertex, an obliquely (but precipitously) sloping frontal adjacent to vertex, anteriorly directed and short zygomatic processes, and squamosal creases. -
Faults and Joints
133 JOINTS Joints (also termed extensional fractures) are planes of separation on which no or undetectable shear displacement has taken place. The two walls of the resulting tiny opening typically remain in tight (matching) contact. Joints may result from regional tectonics (i.e. the compressive stresses in front of a mountain belt), folding (due to curvature of bedding), faulting, or internal stress release during uplift or cooling. They often form under high fluid pressure (i.e. low effective stress), perpendicular to the smallest principal stress. The aperture of a joint is the space between its two walls measured perpendicularly to the mean plane. Apertures can be open (resulting in permeability enhancement) or occluded by mineral cement (resulting in permeability reduction). A joint with a large aperture (> few mm) is a fissure. The mechanical layer thickness of the deforming rock controls joint growth. If present in sufficient number, open joints may provide adequate porosity and permeability such that an otherwise impermeable rock may become a productive fractured reservoir. In quarrying, the largest block size depends on joint frequency; abundant fractures are desirable for quarrying crushed rock and gravel. Joint sets and systems Joints are ubiquitous features of rock exposures and often form families of straight to curviplanar fractures typically perpendicular to the layer boundaries in sedimentary rocks. A set is a group of joints with similar orientation and morphology. Several sets usually occur at the same place with no apparent interaction, giving exposures a blocky or fragmented appearance. Two or more sets of joints present together in an exposure compose a joint system. -
Western States Seismic Policy Council Policy Recommendation 18-3
WESTERN STATES SEISMIC POLICY COUNCIL POLICY RECOMMENDATION 18-3 Definitions of Recency of Surface Faulting for the Basin and Range Province Policy Recommendation 18-3 WSSPC recommends that each state in the Basin and Range physiographic province (BRP), through consultation with state and federal geological surveys and other earthquake-hazard experts, define scientifically and societally relevant categories for recency of surface faulting (generally earthquake magnitude ≥M 6.5). WSSPC further recommends that in the absence of information to the contrary, all Quaternary faults be considered to have the recency of activity documented in the USGS Quaternary fault and fold database until more adequate data can be developed. Executive Summary Fault recency definitions are limited to the Quaternary because this period of geologic time is considered by the scientific community to be most relevant to paleoseismic studies of earthquake faults (Machette and others, 2004). The recency class of a fault is the youngest class based on the demonstrated age of most recent surface faulting. Latest Pleistocene-Holocene faults are included within the definition of late Quaternary faults, and both latest Pleistocene-Holocene and late Quaternary faults are included in Quaternary faults. Establishment/definition of surface-faulting recency categories are based on the ways that faults are portrayed on geologic maps and on the availability of geologic data in the BRP. Policy makers (owners, regulators, governmental agencies) should consult with state and federal geological surveys and other earthquake-hazard experts in using these recency categories and additional geologic data in developing definitions of hazardous faults to be considered in planning for development or infrastructure projects. -
5 Geologic and Geotechnical Assessments
5 Geologic and Geotechnical Assessments 5.1 Regional and Site Geology Gilpin Geosciences, Inc. assessed the site conditions and prepared an engineering geologic evaluation of the project area, which is included as Appendix D. The site is located in the Coast Ranges geomorphic province that is characterized by northwest-southeast trending valleys and ridges. These are controlled by folds and faults that resulted from the collision of the Farallon and North American plates and subsequent shearing along the San Andreas Fault. The Merced Formation crops out in a broad trough that is partially exposed along the coastal bluffs of the site vicinity. It is of Plio-Pleistocene age (5 million to 10,000 years ago) and is characterized by sands and fine-grained deposits deposited in near-shore ocean environments with some units deposited onshore as dune fields. It is mapped as filling a northwest-southeast trending, fault-bounded basin that is exposed for approximately 3.8 miles along the sea cliffs from Mussel Rock on the south to the north end of Lake Merced. The Merced Formation is overlain by the Late Pleistocene age (125,000 to 10,000 years ago) Colma Formation, which is composed of sandy near-shore and beach deposits and recent dune sands. Several investigators have mapped the Merced Formation in the bluffs in the site vicinity. Hall (1966 and 1967) and Clifton and Hunter (1987) mapped the Merced Formation in detail to understand the age range and rapid changes in depositional environments preserved in the deposits outcropping along the Fort Funston / Thornton Beach coastal bluffs. -
Late Quaternary Faulting in the Kaikoura Region, Southeastern Marlborough, New Zealand
AN ABSTRACT OF THE THESIS OF Russell J. Van Dissen for the degree of Master of Science in Geology presented on February 15, 1989. Title: Late Quaternary Faulting in the Kaikoura Region, Southeastern Marlborough, New Zealand Redacted for privacy Abstract approved: Dr. Robert 8.0eats Active faults in the Kaikoura region include the Hope, Kekerengu, and Fidget Faults, and the newly discovered Jordan Thrust, Fyffe, and Kowhai Faults. Ages of faulted alluvial terraces along the Hope Fault and the Jordan Thrust were estimated using radiocarbon-calibrated weathering-rind measurements on graywacke clasts. Within the study area, the Hope Fault is divided, from west to east, into the Kahutara, Mt. Fyffe, and Seaward segments. The Kahutara segment has a relatively constant Holocene right-lateral slip rate of 20-32 mm/yr, and an earthquake recurrence interval of 86 to 600 yrs: based on single-event displacements of 3 to 12 m. The western portion of the Mt. Fyffe segment has a minimum Holocene lateral slip rate of 16 + 5 mm/yr .(southeast side up); the eastern portion has horizontal and vertical slip rates of 4.8+ 2.7 mm/yr and 1.7 + 0.2 mm/yr, respectively (northwest side up). There is no dated evidence for late Quaternary movementon the Seaward segment, and its topographic expression is much more subdued than that of the two western segments. The Jordan Thrust extends northeast from the Hope Fault, west of the Seaward segment. The thrust has horizontal and vertical slip rates of 2.2 + 1.3 mm/yr and 2.1 + 0.5 mm/yr, respectively (northwest side up), and a maximum recurrence interval of 1200 yrs: based on 3 events within the last 3.5 ka. -
Present Day Plate Boundary Deformation in the Caribbean and Crustal Deformation on Southern Haiti Steeve Symithe Purdue University
Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations 4-2016 Present day plate boundary deformation in the Caribbean and crustal deformation on southern Haiti Steeve Symithe Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Caribbean Languages and Societies Commons, Geology Commons, and the Geophysics and Seismology Commons Recommended Citation Symithe, Steeve, "Present day plate boundary deformation in the Caribbean and crustal deformation on southern Haiti" (2016). Open Access Dissertations. 715. https://docs.lib.purdue.edu/open_access_dissertations/715 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Graduate School Form 30 Updated ¡ ¢¡£ ¢¡¤ ¥ PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance This is to certify that the thesis/dissertation prepared By Steeve Symithe Entitled Present Day Plate Boundary Deformation in The Caribbean and Crustal Deformation On Southern Haiti. For the degree of Doctor of Philosophy Is approved by the final examining committee: Christopher L. Andronicos Chair Andrew M. Freed Julie L. Elliott Ayhan Irfanoglu To the best of my knowledge and as understood by the student in the Thesis/Dissertation Agreement, Publication Delay, and Certification Disclaimer (Graduate School Form 32), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy of Integrity in Research” and the use of copyright material. Andrew M. Freed Approved by Major Professor(s): Indrajeet Chaubey 04/21/2016 Approved by: Head of the Departmental Graduate Program Date PRESENT DAY PLATE BOUNDARY DEFORMATION IN THE CARIBBEAN AND CRUSTAL DEFORMATION ON SOUTHERN HAITI A Dissertation Submitted to the Faculty of Purdue University by Steeve J. -
Composition, Alteration, and Texture of Fault-Related Rocks from Safod Core and Surface Outcrop Analogs
Pure Appl. Geophys. Ó 2014 Springer Basel DOI 10.1007/s00024-014-0896-6 Pure and Applied Geophysics Composition, Alteration, and Texture of Fault-Related Rocks from Safod Core and Surface Outcrop Analogs: Evidence for Deformation Processes and Fluid-Rock Interactions 1 1 1 1 1 KELLY K. BRADBURY, COLTER R. DAVIS, JOHN W. SHERVAIS, SUSANNE U. JANECKE, and JAMES P. EVANS Abstract—We examine the fine-scale variations in mineralogi- 1. Introduction cal composition, geochemical alteration, and texture of the fault- related rocks from the Phase 3 whole-rock core sampled between 3,187.4 and 3,301.4 m measured depth within the San Andreas Fault Well-constrained geological, geochemical, and Observatory at Depth (SAFOD) borehole near Parkfield, California. geophysical models of active fault zones are needed if This work provides insight into the physical and chemical properties, we are to understand fault zone behavior and earth- structural architecture, and fluid-rock interactions associated with the actively deforming traces of the San Andreas Fault zone at depth. quake deformation, constraining the factors that affect Exhumed outcrops within the SAF system comprised of serpentinite- the distribution of earthquakes, and the nature of slip bearing protolith are examined for comparison at San Simeon, Goat in the shallow crust by developing realistic models of Rock State Park, and Nelson Creek, California. In the Phase 3 SAFOD drillcore samples, the fault-related rocks consist of multiple subsurface fault zone structure and ground motion juxtaposed lenses of sheared, foliated siltstone and shale with block- predictions. Earthquakes nucleate in rocks at depth in-matrix fabric, black cataclasite to ultracataclasite, and sheared (e.g., FAGERENG and TOY 2011;SIBSON 1977; 2003), serpentinite-bearing, finely foliated fault gouge. -
A GPS and Modelling Study of Deformation in Northern Central America
Geophys. J. Int. (2009) 178, 1733–1754 doi: 10.1111/j.1365-246X.2009.04251.x A GPS and modelling study of deformation in northern Central America M. Rodriguez,1 C. DeMets,1 R. Rogers,2 C. Tenorio3 and D. Hernandez4 1Geology and Geophysics, University of Wisconsin-Madison, Madison, WI 53706 USA. E-mail: [email protected] 2Department of Geology, California State University Stanislaus, Turlock, CA 95382,USA 3School of Physics, Faculty of Sciences, Universidad Nacional Autonoma de Honduras, Tegucigalpa, Honduras 4Servicio Nacional de Estudios Territoriales, Ministerio de Medio Ambiente y Recursos Naturales, Km. 5 1/2 carretera a Santa Tecla, Colonia y Calle Las Mercedes, Plantel ISTA, San Salvador, El Salvador Accepted 2009 May 9. Received 2009 May 8; in original form 2008 August 15 SUMMARY We use GPS measurements at 37 stations in Honduras and El Salvador to describe active deformation of the western end of the Caribbean Plate between the Motagua fault and Central American volcanic arc. All GPS sites located in eastern Honduras move with the Caribbean Plate, in accord with geologic evidence for an absence of neotectonic deformation in this region. Relative to the Caribbean Plate, the other stations in the study area move west to west–northwest at rates that increase gradually from 3.3 ± 0.6 mm yr−1 in central Honduras to 4.1 ± 0.6 mm yr−1 in western Honduras to as high as 11–12 mm yr−1 in southern Guatemala. The site motions are consistent with slow westward extension that has been inferred by previous authors from the north-striking grabens and earthquake focal mechanisms in this region. -
Gy403 Structural Geology Kinematic Analysis Kinematics
GY403 STRUCTURAL GEOLOGY KINEMATIC ANALYSIS KINEMATICS • Translation- described by a vector quantity • Rotation- described by: • Axis of rotation point • Magnitude of rotation (degrees) • Sense of rotation (reference frame; clockwise or anticlockwise) • Dilation- volume change • Loss of volume = negative dilation • Increase of volume = positive dilation • Distortion- change in original shape RIGID VS. NON-RIGID BODY DEFORMATION • Rigid Body Deformation • Translation: fault slip • Rotation: rotational fault • Non-rigid Body Deformation • Dilation: burial of sediment/rock • Distortion: ductile deformation (permanent shape change) TRANSLATION EXAMPLES • Slip along a planar fault • 360 meters left lateral slip • 50 meters normal dip slip • Classification: normal left-lateral slip fault 30 Net Slip Vector X(S) 40 70 N 50m dip slip X(N) 360m strike slip 30 40 0 100m ROTATIONAL FAULT • Fault slip is described by an axis of rotation • Rotation is anticlockwise as viewed from the south fault block • Amount of rotation is 50 degrees Axis W E 50 FAULT SEPARATION VS. SLIP • Fault separation: the apparent slip as viewed on a planar outcrop. • Fault slip: must be measured with net slip vector using a linear feature offset by the fault. 70 40 150m D U 40 STRAIN ELLIPSOID X • A three-dimensional ellipsoid that describes the magnitude of dilational and distortional strain. • Assume a perfect sphere before deformation. • Three mutually perpendicular axes X, Y, and Z. • X is maximum stretch (S ) and Z is minimum stretch (S ). X Z Y Z • There are unique directions